arch/arm/mach-ep93xx/include/mach/uncompress.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * arch/arm/mach-ep93xx/include/mach/uncompress.h
   4  *
   5  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
   6  */
   7
   8 #include <mach/ep93xx-regs.h>
   9 #include <asm/mach-types.h>
  10
  11 static unsigned char __raw_readb(unsigned int ptr)
  12 {
  13         return *((volatile unsigned char *)ptr);
  14 }
  15
  16 static unsigned int __raw_readl(unsigned int ptr)
  17 {
  18         return *((volatile unsigned int *)ptr);
  19 }
  20
  21 static void __raw_writeb(unsigned char value, unsigned int ptr)
  22 {
  23         *((volatile unsigned char *)ptr) = value;
  24 }
  25
  26 static void __raw_writel(unsigned int value, unsigned int ptr)
  27 {
  28         *((volatile unsigned int *)ptr) = value;
  29 }
  30
  31 #define PHYS_UART_DATA          (CONFIG_DEBUG_UART_PHYS + 0x00)
  32 #define PHYS_UART_FLAG          (CONFIG_DEBUG_UART_PHYS + 0x18)
  33 #define UART_FLAG_TXFF          0x20
  34
  35 static inline void putc(int c)
  36 {
  37         int i;
  38
  39         for (i = 0; i < 10000; i++) {
  40                 /* Transmit fifo not full? */
  41                 if (!(__raw_readb(PHYS_UART_FLAG) & UART_FLAG_TXFF))
  42                         break;
  43         }
  44
  45         __raw_writeb(c, PHYS_UART_DATA);
  46 }
  47
  48 static inline void flush(void)
  49 {
  50 }
  51
  52
  53 /*
  54  * Some bootloaders don't turn off DMA from the ethernet MAC before
  55  * jumping to linux, which means that we might end up with bits of RX
  56  * status and packet data scribbled over the uncompressed kernel image.
  57  * Work around this by resetting the ethernet MAC before we uncompress.
  58  */
  59 #define PHYS_ETH_SELF_CTL               0x80010020
  60 #define ETH_SELF_CTL_RESET              0x00000001
  61
  62 static void ethernet_reset(void)
  63 {
  64         unsigned int v;
  65
  66         /* Reset the ethernet MAC.  */
  67         v = __raw_readl(PHYS_ETH_SELF_CTL);
  68         __raw_writel(v | ETH_SELF_CTL_RESET, PHYS_ETH_SELF_CTL);
  69
  70         /* Wait for reset to finish.  */
  71         while (__raw_readl(PHYS_ETH_SELF_CTL) & ETH_SELF_CTL_RESET)
  72                 ;
  73 }
  74
  75 #define TS72XX_WDT_CONTROL_PHYS_BASE    0x23800000
  76 #define TS72XX_WDT_FEED_PHYS_BASE       0x23c00000
  77 #define TS72XX_WDT_FEED_VAL             0x05
  78
  79 static void __maybe_unused ts72xx_watchdog_disable(void)
  80 {
  81         __raw_writeb(TS72XX_WDT_FEED_VAL, TS72XX_WDT_FEED_PHYS_BASE);
  82         __raw_writeb(0, TS72XX_WDT_CONTROL_PHYS_BASE);
  83 }
  84
  85 static void arch_decomp_setup(void)
  86 {
  87         if (machine_is_ts72xx())
  88                 ts72xx_watchdog_disable();
  89         ethernet_reset();
  90 }